TRANSFERS BY LEAGUE

However, Arsenal fans will not have spent the night partying in the streets of Islington. Deadline day could not be regarded as a complete success, as the Gunners failed to add the defensive players they badly needed.

The acquisition of Welbeck looks to be an astute one. The England international is a player of enormous potential who has been squeezed out of the Old Trafford reckoning by the arrival of Radamel Falcao.

Some Arsenal fans may feel aggrieved that they have not landed a marquee name of their own, but the reality is that Arsene Wenger was never likely to shatter the club's wage structure to bring in someone like Falcao. The Colombian will turn 29 before the season is out and recently suffered a very serious knee injury.

Welbeck might not offer the same goal threat, but he is younger, fitter and more versatile. In many respects, he is a classic Wenger purchase.

Despite his versatility, Welbeck is surely joining Arsenal to play as a centre-forward. Giroud's injury has created a vacancy in the starting XI.

Yaya Sanogo auditioned for the part on Sunday at Leicester and was wholly unconvincing. Now, Welbeck will get his chance to stake his claim for a regular berth in his preferred position.

He appears to be an immediate upgrade on Sanogo. Welbeck is more mobile, quicker in the sprint and blessed with better technique. He can be uncouth in front of goal, but that seems a churlish complaint when the alternative is a player who has yet to score a competitive Arsenal goal in 17 appearances.

Welbeck is somewhat reminiscent of a young Emmanuel Adebayor. He has plenty of ability and athleticism but lacks composure in front of goal.

Under Wenger, Adebayor's finishing evolved from erratic to accomplished. If Wenger can pull off the same trick with Welbeck, Arsenal will have assuaged their attacking problems.

At the back, however, things don't look quite so rosy.

The team's squad page lists just six first-team defenders.

Given the Gunners typically play with four at the back, that's a worrying lack of depth. Currently, both Laurent Koscielny and Kieran Gibbs are out injured, meaning Wenger doesn't have a single senior defender in reserve.

It's difficult to understand just how Arsenal failed to recruit a new defender. Thomas Vermaelen was sold on Aug. 9, but Wenger knew he needed a new centre-half long before that.

Last season, Arsenal were fortunate to get away with having just three senior central defenders. This time round, they have only the teenage Calum Chambers to fill in for the first-choice pairing of Per Mertesacker and Laurent Koscielny. For all his promise, Chambers is still a novice -- unfortunately, mistakes are inevitable.

Arsenal fans had also hoped for the arrival of a new holding midfielder, with excited talk of Portuguese international William Carvalho.

That particular deal never materialised, but the supporters' disappointment faded into insignificance amid concerns over Arsenal's lack of defensive depth. Gunners fans will be praying their back four can avoid injuries until at least January, when the market reopens.

In the cold light of day, there will be relief that Arsenal have added a powerful attacker to provide cover for Giroud.

However, that boon merely highlights the huge imbalance in the Arsenal squad. Wenger now has options up top but absolutely no room for manoeuvre at the back.

Arsenal's failure to add to their defensive ranks could come back to haunt them.

James McNicholas is one of ESPN FC's Arsenal bloggers. You can follow him on Twitter @gunnerblog.